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.Dd November 24, 2017
.Dt sysdecode_kevent 3
.Os
.Sh NAME
.Nm sysdecode_kevent ,
.Nm sysdecode_kevent_fflags ,
.Nm sysdecode_kevent_filter ,
.Nm sysdecode_kevent_flags
.Nd output description of kevent structure fields
.Sh LIBRARY
.Lb libsysdecode
.Sh SYNOPSIS
.In sysdecode.h
.Ft void
.Fn sysdecode_kevent_fflags "FILE *fp" "short filter" "int fflags" "int base"
.Ft bool
.Fn sysdecode_kevent_flags "FILE *fp" "int flags" "int *rem"
.Ft const char *
.Fn sysdecode_kevent_filter "int filter"
.Sh DESCRIPTION
These functions provide text descriptions of
.Vt struct kevent
fields.
.Pp
The
.Fn sysdecode_kevent_fflags
function outputs a text description of the
.Fa fflags
member of a
.Vt struct kevent
to the stream
.Fa fp .
For the
.Dv EVFILT_READ ,
.Dv EVFILT_WRITE ,
.Dv EVFILT_VNODE ,
.Dv EVFILT_PROC ,
.Dv EVFILT_PROCDESC ,
.Dv EVFILT_TIMER ,
and
.Dv EVFILT_USER
filters,
.Fn sysdecode_kevent_fflags
outputs a bitmask of filter-specific
.Dv NOTE_*
flags as documented in
.Xr kevent 2 .
For other values of
.Fa filter ,
the value of
.Fa fflags
is output in the indicated
.Fa base
.Pq one of 8, 10, or 16 .
.Pp
The
.Fn sysdecode_kevent_filter
function returns a text description of the
.Fa filter
member of a
.Vt struct kevent .
.Dv NULL
is returned if the
.Fa filter
value is unknown.
.Pp
The
.Fn sysdecode_kevent_flags
function outputs a text description of the
.Fa flags
member of a
.Vt struct kevent
to the stream
.Fa fp .
This function uses the same calling convention and formatting as the other
functions described in
.Xr sysdecode_mask 3 .
.Sh RETURN VALUES
The
.Nm sysdecode_kevent_filter
function returns the name of a filter or
.Dv NULL if the filter value is unknown.
.Pp
The
.Nm sysdecode_kevent_flags
function returns
.Dv true
if any flags in the
.Fa flags
field were decoded and
.Dv false
if no flags were decoded.
.Sh SEE ALSO
.Xr sysdecode 3 ,
.Xr sysdecode_enum 3 ,
.Xr sysdecode_mask 3
